Библиотека института физики им. Л.В. Киренского СО РАН

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Каталог книг и брошюр библиотеки ИФ СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Stepin E. A., Sushko E. S., Vnukova N. G., Churilov G. N., Rogova A. V., Tomilin F. N., Kudryasheva N. S.
Заглавие : Effects of endohedral Gd-containing fullerenols with a different number of oxygen substituents on bacterial bioluminescence
Колич.характеристики :19 с
Место публикации : Int. J. Mol. Sci. - 2024. - Vol. 25, Is. 2. - Ст.708. - ISSN 16616596 (ISSN), DOI 10.3390/ijms25020708. - ISSN 14220067 (eISSN)
Примечания : Cited References: 102. - This research was funded by the State Assignment of the Ministry of Science and Higher Education of the Russian Federation, project No. 0287-2021-0020, and partly supported by the Russian Science Foundation No. 23-26-10018, Krasnoyarsk Regional Science Foundation
Аннотация: Gadolinium (Gd)-containing fullerenols are perspective agents for magnetic resonance imaging and cancer research. They combine the unique paramagnetic properties of Gd with solubility in water, low toxicity and antiradical activity of fullerenols. We compared the bioeffects of two Gd-containing fullerenols with a different number of oxygen groups—20 and 42: Gd@C82O20H14 and Gd@C82O42H32. The bioluminescent bacteria-based assay was applied to monitor the toxicity of fullerenols, bioluminescence was applied as a signal physiological parameter, and bacterial enzyme-based assay was used to evaluate the fullerenol effects on enzymatic intracellular processes. Chemiluminescence luminol assay was applied to monitor the content of reactive oxygen species (ROS) in bacterial and enzymatic media. It was shown that Gd@C82O42H32 and Gd@C82O20H14 inhibited bacterial bioluminescence at 10?1 and 10?2 gL?1, respectively, revealing a lower toxicity of Gd@C82O42H32. Low-concentration (10?3–10?1 gL?1) bacterial bioluminescence activation by Gd@C82O42H32 was observed, while this activation was not found under exposure to Gd@C82O20H14. Additional carboxyl groups in the structure of Gd@C82O42H32 were determined by infrared spectroscopy and confirmed by quantum chemical calculations. The groups were supposed to endow Gd@C82O42H32 with higher penetration ability through the cellular membrane, activation ability, lower toxicity, balancing of the ROS content in the bacterial suspensions, and lower aggregation in aqueous media.
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Вид документа : Статья из журнала
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Автор(ы) : Wang, Xuejiao, Feng, Xiaowen, Molokeev M. S., Zheng, Huiling, Wang, Qiushi, Xu, Chunyan, Li, Ji-Guang
Заглавие : Modulation of Bi3+ luminescence from broadband green to broadband deep red in Lu2WO6 by Gd3+ doping and its applications in high color rendering index white LED and near-infrared LED
Место публикации : Dalton Trans. - 2023. - Vol. 52, Is. 9. - P.2619-2630. - ISSN 14779226 (ISSN), DOI 10.1039/D2DT03751C. - ISSN 14779234 (eISSN)
Примечания : Cited References: 4. - This work is supported in part by the Project of Education Department of Liaoning Province (Grant No. LQ2019014) and he Natural Science Foundation of Liaoning Province (Grant No. 2020-MS-286). The authors are thankful for the support for the 4B9A Beamline from the Beijing Synchrotron Radiation Facility (BSRF) (Project No. 2021-BEPC-PT-005290). The authors would like to thank Siqi Liu from Shiyanjia Lab (
Аннотация: Phosphors that exhibit tunable broadband emissions are highly desired in multi-functional LEDs, including pc-WLEDs and pc-NIR LEDs. In this work, broadband emissions were obtained and modulated in the unexpectedly wide spectral range of 517–609 nm for (Lu0.99−xGdxBi0.01)2WO6 phosphors by tuning the Gd3+ content (x = 0–0.99). The effects of Gd3+ doping on phase constituents, particle morphology, crystal structure, and photoluminescence were systematically investigated. Broadband green emission was obtained from Gd3+-free (Lu0.99Bi0.01)2WO6 phosphors (x = 0), whose emission intensity was enhanced by 50% with 5 at% Gd3+ (x = 0.05). The phase transition happened when x 0.50 and the broadband red-NIR emission was obtained when x = 0.75–0.99. Three luminescence centers were proved to be responsible for the broadband green emissions via crystal structure, spectral fitting and fluorescence decay analysis. A pc-WLED with a high color rendering index (Ra = 91.3), a stable emission color, and a low color temperature (3951 K) was fabricated from the (Lu0.94Gd0.05Bi0.01)2WO6 broadband green phosphor, and an LED device that simultaneously emits high color rendering index white light and NIR light was obtained with the (Gd0.99Bi0.01)2WO6 broadband red-NIR phosphor. Night vision and noninvasive imaging were also demonstrated using the latter LED device.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Tomilin F. N., Artyushenko P. V., Shchugoreva I. A., Rogova A. V., Vnukova N. G., Churilov G. N., Shestakov N. P., Tchaikovskaya O. N., Ovchinnikov S. G., Avramov P. V.
Заглавие : Structure and vibrational spectroscopy of C82 fullerenol valent isomers: An experimental and theoretical joint study
Место публикации : Molecules. - 2023. - Vol. 28, Is. 4. - Ст.1569. - ISSN 14203049 (eISSN), DOI 10.3390/molecules28041569
Примечания : Cited References: 57. - Synthesis and spectroscopic study of the Gd@C82OxHy complexes were supported by the Ministry of Science and Higher Education of the Russian Federation under project FWES-2022-0005. Molecular design of the fullerene derivatives was supported by the National Research Foundation of the Republic of Korea, grant NRF 2021R1A2C1010455. DFTB3 electronic structure calculations were supported by Project FSWM-2020-0033 of the Russian Ministry of Science and Education
Аннотация: Gd@C82OxHy endohedral complexes for advanced biomedical applications (computer tomography, cancer treatment, etc.) were synthesized using high-frequency arc plasma discharge through a mixture of graphite and Gd2O3 oxide. The Gd@C82 endohedral complex was isolated by high-efficiency liquid chromatography and consequently oxidized with the formation of a family of Gd endohedral fullerenols with gross formula Gd@C82O8(OH)20. Fourier-transformed infrared (FTIR) spectroscopy was used to study the structure and spectroscopic properties of the complexes in combination with the DFTB3 electronic structure calculations and infrared spectra simulations. It was shown that the main IR spectral features are formed by a fullerenole C82 cage that allows one to consider the force constants at the DFTB3 level of theory without consideration of gadolinium endohedral ions inside the carbon cage. Based on the comparison of experimental FTIR and theoretical DFTB3 IR spectra, it was found that oxidation of the C82 cage causes the formation of Gd@C82O28H20, with a breakdown of the integrity of the parent C82 cage with the formation of pores between neighboring carbonyl and carboxyl groups. The Gd@C82O6(OOH)2(OH)18 endohedral complex with epoxy, carbonyl and carboxyl groups was considered the most reliable fullerenole structural model.
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Вид документа : Статья из журнала
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Автор(ы) : Abulkhaev M. U., Molokeev M. S., Oreshonkov A. S., Aleksandrovsky A. S., Kertman A. V., Kamaev D. N., Trofimova O. V., Elyshev A. V., Andreev O. V.
Заглавие : Properties of GdSF and phase diagram of the GdF3 - Gd2S3 system
Место публикации : J. Solid State Chem. - 2023. - Vol. 322. - Ст.123991. - ISSN 00224596 (ISSN), DOI 10.1016/j.jssc.2023.123991. - ISSN 1095726X (eISSN)
Примечания : Cited References: 44. - The authors of the article are grateful to P.P. Fedorov for valuable critical comments on the manuscriptThis research was funded by the Tyumen Oblast Government, as a part of the West-Siberian Interregional Science and Education Center’s project No. 89-DON (3)
Аннотация: The objectives of this study were to refine the phase diagram of the GdF3-Gd2S3 system and to calculate their liquidus, and to synthesize GdSF and to study their properties. The GdSF compound (ST PbFCl, P4/nmm, a (Å) 3.83006(17), c (Å) 6.8529(3), has an optical band gap for a direct interband transition of 2.56 eV and is characterized by a pronounced increase in the Kubelka-Munk function in the region of this transition. Direct optical bandgap of GdSF is measured to be equal to 2.77 eV. Two indirect bandgaps are detected to be 1.54 and 2.4 eV. Meta-GGA simulations of band structure predicting 1.481 eV direct bandgap of GdSF are in good agreement with these features of the experimental absorption spectrum. To explain this complicated case, we argue that formally direct optical transitions to highly dispersive subbands contribute not to direct but to indirect bandgaps measured by Tauc analysis. The GdSF compound melts incongruently with the formation of a melt and γ-Gd2S3 compound at t = 1280 ± 2°С, ΔН = 40.6 ± 2.8 kJ/mol, ΔS = 26.1 ± 1.8 J/mol∗K. The eutectic has a composition of 13 mol.% Gd2S3 (0.74 GdF3 + 0.26 GdSF), the melting characteristics of the eutectic are 1182 ± 2°С, ΔН = 36.2 ± 2.5 kJ/mol, ΔS = 24.9 ± 1.7 J/mol∗K. In the system GdF3 - Gd2S3 the balance equations for five phase transformations recorded by the DSC method were compiled. Convergence was achieved in the liquidus of the system constructed according to DSC data and calculated with the use of the Redlich-Kister equation.
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Вид документа : Статья из журнала
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Автор(ы) : Gao P. -X., Dong P., Zhou Z. -Y., Zhang X. -J., Li Y. -N., Yang J. -K., Li Q., Chen K., Molokeev M. S., Zhou Z., Xia M.
Заглавие : Novel far-red phosphors (La, Gd, Y)2MgTiO6:Cr3+ with tunable luminescence spectra for grow light
Разночтения заглавия :
Место публикации : Faguang Xuebao/Chin. J. Lumines. - 2022. - Vol. 43, Is. 1. - P.58-68. - ISSN 10007032 (ISSN), DOI 10.37188/CJL.20210327
Примечания : Cited References: 27. - Supported by National Natural Science Foundation of China(51974123); The Distinguished Youth Foundation of Hunan Province(2020JJ2018); Key R & D Projects in Hunan Province(2020WK2016&2020SK2032&2022NK2044), Hunan High Level Talent Gathering Project(2019RS1077&2020RC5007); Natural Science Foundation of Hunan Province(2021JJ40261); The Scientific Research Fund of Hunan Provincial Education Department(19C0903); The Natural Sciences Foundation of Hunan Agricultural University(19QN11); Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Resource Utilization Science Foundation(19KFXM12); Changsha Science and Technology Plan(KH2005114)
Аннотация: Cr3+-activated double perovskite structure phosphor has drawn wide attention due to its far-red and near-infrared emission. In this work, we synthesized a series of (La,Gd,Y)2MgTiO6∶Cr3+ phosphors which can be excited by ultraviolet light of about 345 nm, and the emission bands are in the range of 700-900 nm. The spectra were tuned by ions substitution strategy. The main emission peaks were blue shifted from 766 nm to 737 nm and 757 nm by substituting the La site with Gd and Y, respectively. Meanwhile, the thermal stability at 150 ℃ increased from 41.7% to 69.1% and 67%, respectively. The crystal structure, microstructure, decay time, thermal stability and band gap were investigated systematically. The substitution of Gd/Y ions causes the lattice contraction, which results in the change of the nephelauxetic effect, and eventually leads to the blue shift of the spectra. The emission spectra of these phosphors have good matching with the 730 nm absorption peak of phytochrome FR(PFR), indicating their application prospect in plant growth lighting. Cationic substitution strategy can regulate the luminescence properties of Cr3+, which provides ideas for the development of phosphors for plant growth lamps in the future.
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Вид документа : Статья из журнала
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Автор(ы) : Andreev O. V., Atuchin V. V., Aleksandrovsky A. S., Denisenko Y. G., Zakharov B. A., Tyutyunnik A. P., Habibullayev N. N., Velikanov D. A., Ulybin D. A., Shpindyuk D. D.
Заглавие : Synthesis, structure, and properties of EuLnCuSe3 (Ln = Nd, Sm, Gd, Er)
Коллективы : Ministry of Science and Higher Education of the Russian Ferderation [AAAA-A21-121011390011-4, AAAA-A19-119031890025-9]; Government of the Tyumen Region [2. 89-don]
Место публикации : Crystals. - 2022. - Vol. 12, Is. 1. - Ст.17. - ISSN 2073-4352(eISSN), DOI 10.3390/cryst12010017
Примечания : Cited References: 60. - The study was funded by the Ministry of Science and Higher Education of the Russian Ferderation (Projects AAAA-A21-121011390011-4 and AAAA-A19-119031890025-9), as well as the Government of the Tyumen Region (grant to non-profit organizations No. 2. 89-don, dated 7 December 2020)
Предметные рубрики: RARE-EARTH
CRYSTAL-STRUCTURE
MAGNETIC-PROPERTIES
CHALCOGENIDES
Аннотация: EuLnCuSe3 (Ln = Nd, Sm, Gd, Er), due to their complex composition, should be considered new materials with the ability to purposefully change the properties. Samples of the EuLnCuSe3 were prepared using Cu, rare earth metal, Se (99.99%) by the ampoule method. The samples were obtained by the crystallization from a melt and annealed at temperatures 1073 and 1273 K. The EuErCuSe3 crystal structure was established using the single-crystal particle. EuErCuSe3 crystallizes in the orthorhombic system, space group Cmcm, KCuZrS3 structure type, with cell parameters a = 4.0555 (3), b = 13.3570 (9), and c = 10.4602 (7) Å, V = 566.62 (6) Å3. In structure EuErCuSe3, erbium ions are coordinated by selenium ions in the octahedral polyhedron, copper ions are in the tetrahedral coordination, europium ions are between copper and erbium polyhedra layers and are coordinated by selenium ions as two-cap trigonal prisms. The optical band gap is 1.79 eV. At 4.7 K, a transition from the ferrimagnetic state to the paramagnetic state was detected in EuErCuSe3. At 85 and 293 K, the compound is in a paramagnetic state. According to XRPD data, EuLnCuSe3 (Ln = Nd, Sm, Gd) compounds have a Pnma orthorhombic space group of the Eu2CuS3 structure type. For EuSmCuSe3, a = 10.75704 (15) Å, b = 4.11120 (5) Å, c = 13.37778 (22) Å. In the series of EuLnCuSe3 compounds, the optical band gap increases 1.58 eV (Nd), 1.58 eV (Sm), 1.72 eV (Gd), 1.79 eV (Er), the microhardness of the 205 (Nd), 210 (Sm), 225 (Gd) 235 ± 4 HV (Er) phases increases, and the thermal stability of the phases increases significantly. According to the measurement data of differential scanning calorimetry, the EuNdCuSe3 decomposes, according to the solid-phase reaction T = 1296 K, ΔH = 8.2 ± 0.8 kJ/mol. EuSmCuSe3 melts incongruently T = 1449 K, ΔH = 18.8 ± 1.9 kJ/mol. For the EuGdCuSe3, two (Tα↔β = 1494 K, ΔHα↔β = 14.8 kJ/mol, Tβ↔γ = 1530 K, ΔHβ↔γ = 4.8 kJ/mol) and for EuErCuSe3 three polymorphic transitions (Tα↔β = 1561 K, ΔHα↔β = 30.3 kJ/mol, Tβ↔γ = 1579 K, ΔHβ↔γ = 4.4 kJ/mol, and Tγ↔δ = 1600 K, ΔHγ↔δ = 10.1 kJ/mol). The compounds melt incongruently at the temperature of 1588 K, ΔHmelt = 17.9 ± 1.8 kJ/mol and 1664 K, ΔHmelt = 25.6 ± 2.5 kJ/mol, respectively. Incongruent melting of the phases proceeds with the formation of a solid solution of EuSe and a liquid phase.
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Вид документа : Статья из журнала
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Автор(ы) : Sushko E. S., Vnukova N. G., Churilov G. N., Kudryasheva N. S.
Заглавие : Endohedral Gd-containing fullerenol: Toxicity, antioxidant activity and regulation of reactive oxygen species in cellular and enzymatic systems
Место публикации : Int. J. Mol. Sci. - 2022. - Vol. 23, Is. 9. - Ст.5152. - ISSN 16616596 (ISSN), DOI 10.3390/ijms23095152
Примечания : Cited References: 117. - This research was funded by Russian Foundation for Basic Research, N18-29-19003; Russian Foundation for Basic Research, Krasnoyarsk Territory and Krasnoyarsk Regional Fund of Science, N20-44-243001; and partly supported by the Program of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Fundamental Study 2020-2025 (Russia)
Аннотация: The Gd-containing metallofullerene derivatives are perspective magnetic resonance imaging contrast agents. We studied the bioeffects of a water-soluble fullerene derivative, gadolinium-endohedral fullerenol, with 40–42 oxygen groups (Gd@Fln). Bioluminescent cellular and enzymatic assays were applied to monitor toxicity and antioxidant activity of Gd@Fln in model solutions; bioluminescence was applied as a signaling physiological parameter. The Gd@Fln inhibited bioluminescence at high concentrations (2·10−1 gL−1), revealing lower toxicity as compared to the previously studied fullerenols. Efficient activation of bioluminescence (up to almost 100%) and consumption of reactive oxygen species (ROS) in bacterial suspension were observed under low-concentration exposure to Gd@Fln (10−3–2·10−1 gL−1). Antioxidant capability of Gd@Fln was studied under conditions of model oxidative stress (i.e., solutions of model organic and inorganic oxidizers); antioxidant coefficients of Gd@Fln were determined at different concentrations and times of exposure. Contents of ROS were evaluated and correlations with toxicity/antioxidant coefficients were determined. The bioeffects of Gd@Fln were explained by hydrophobic interactions, electron affinity, and disturbing of ROS balance in the bioluminescence systems. The results contribute to understanding the molecular mechanism of “hormetic” cellular responses. Advantages of the bioluminescence assays to compare bioeffects of fullerenols based on their structural characteristics were demonstrated.
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Вид документа : Статья из журнала
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Автор(ы) : Moshkina E. M., Belskaya N., Bashleev Z., Molokeev M. S., Soloviev L., Shabanova K.
Заглавие : Crystal growth of ReCa3Mn3O3(BO3)4 (Re = Gd, Y) gaudefroyite: Phase sequence and equilibrium study in multi-component fluxes
Место публикации : J. Cryst. Growth. - 2022. - Vol. 600. - Ст.126917. - ISSN 00220248 (ISSN), DOI 10.1016/j.jcrysgro.2022.126917
Примечания : Cited References: 32. - The study was supported by the Russian Science Foundation (grant No. 21-72-00130). The X-ray, and EDX data were obtained using the analytical equipment of the Krasnoyarsk Regional Center of Research Equipment of the Federal Research Center “Krasnoyarsk Science Center SB RAS”
Аннотация: The work is aimed at studying the crystallization of ReCa3Mn3O3(BO3)4 (Re = Gd, Y) borates with the gaudefroyite structure in different flux systems. Gaudefroyites are promising materials in the field of spin ice and magnetocaloric effect. The study has been performed on systems based on the following solvents: Bi2Mo3O12-Na2B4O7-B2O3, Bi2O3-Na2B4O7-B2O3, Bi2O3-BaO-Na2B4O7-B2O3, Li2WO4-Li2O-B2O3. The influence of the solvent components on the sequence of high-temperature crystallizing phases has been studied. The feature of Mo- and W-containing fluxes consisting in the formation of stable chemical bonds of the M2+Mo(W)O4 (M = Ca, Mn) molybdate or tungstate types has been revealed which prevents the formation of gaudefroyite type bonds. An approach has been suggested for changing the sequence of the crystallizing phases which consists in the super saturation of molybdate (tungstate) bonds by Na+ or Li+ cations up to the formation of delafossite-type bonds (Li(Na)-Mn-O phase) with higher manganese valence states Mn3+ and Mn4+. The optimization of the growth conditions of ReCa3(MnO)3(BO3)4 (Re = Gd, Y) gaudefroyite crystals has allowed one to obtain single crystal samples with the size up to 0.8 × 0.8 × 5 mm3. The structural characterization and chemical composition of all the obtained phases are also presented.
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Вид документа : Статья из журнала
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Автор(ы) : Orlov Yu. S., Vereshchagin S. N., Solovyov L. A., Borus A. A., Volochaev M. N., Nikitin A. V., Bushinsky M. V., Lanovsky R. A., Rymski G. S., Dudnikov V. A.
Заглавие : Stability and thermoelectric properties of mechano-activated solid solutions of Sr1-xLnxTiO3-δ (Ln = Nd, Gd, Dy)
Место публикации : J. Taiwan Inst. Chem. Eng. - 2022. - Vol. 138. - Ст.104449. - ISSN 18761070 (ISSN), DOI 10.1016/j.jtice.2022.104449
Примечания : Cited References: 39. - This study was supported by the Russian Foundation for Basic Research, project no. 20-52-04008 Bel_mol_a. Thermal analysis was performed within the scope of Budget Project No. 0287-2021-00-13 for the Institute of Chemistry and Chemical Technology SB RAS
Аннотация: Background: The effect of mechanochemical activation on the microstructure, morphology, and thermoelectric parameters of the materials leading to an increase in the power factor (PF) is demonstrated by the example of the Sr1-xLnxTiO3-δ (Ln = Nd, Gd, Dy; x = 0.05, 0.075, 0.1) solid solutions. Methods: The strontium titanate solid solutions have been synthesized using a conventional ceramic technology from particles of different sizes obtained by mechanical activation of annealed ceramics. Findings: It is shown that different sizes of initial particles cause the morphological and microstructural differences and significantly affect the stability and thermoelectric properties of the synthesized samples. It has been established that a decrease in the initial particle size ensures the thermal stability of the samples and leads to an increase in their electrical conductivity and PF at the minor variation in the Seebeck coefficient. The PF of the Sr0.925Nd0.075TiO3 solid solution changes by a factor of 7. It has been found that the mechanically activated samples have the much lower porosity than the nonactivated ones, which noticeably reduces the effective area of their interaction with the environment (oxygen release and absorption); therefore, all the measurement data obtained on the mechanically activated samples upon their heating and cooling are reversible.
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10.

Вид документа : Статья из журнала
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Автор(ы) : Kostyukov A. I., Snytnikov V. N., Snytnikov V. N., Rakhmanova M. I., Kostyukova N. Y., Ishchenko A. V., Cherepanova S. V., Krylov A. S., Aleksandrovsky A. S.
Заглавие : Synthesis, structure and photoluminescent properties of Eu:Gd2O3 nanophosphor synthesized by cw CO2 laser vaporization
Место публикации : J. Lumines. - 2021. - Vol. 235. - Ст.118050. - ISSN 00222313 (ISSN), DOI 10.1016/j.jlumin.2021.118050
Примечания : Cited References: 42. - The TEM studies are conducted using the equipment of the Center of Collective Use « National Center of Catalyst Research». This work is financially supported by the Russian Foundation for Basic Research (RFBR), Project no. 19-32-60027
Аннотация: Europium doped Gd2O3 sphere-like nanoparticles with dm = 9.3 ± 3.5 nm were synthesized by cw CO2 laser vaporization technique in a flowing mixture of argon and oxygen. According to XRD data, the Eu:Gd2O3 nanoparticles crystallize in the monoclinic symmetry class (C2/m space group). High-resolution luminescence spectroscopy study showed that the ultra-narrow 5D0 → 7F0 transition of Eu3+ demonstrates only two peaks corresponding to two inequivalent Cs positions of Eu3+ ion in monoclinic Gd2O3 lattice that is explained by the peculiarities of local environment of Eu3+ ion at these sites. The hypersensitive transition 5D0 → 7F2 dominates in the spectrum and is expanded to the red part of the spectrum in comparison with cubic Eu:Gd2O3 due to intense transitions terminating at higher-lying components of the crystal-field-split 7F2 state. In the luminescence spectrum, an additional weak band with the maximum at 407 nm corresponding to the electronic transitions 4f65 d1(7FJ) → 4f7(8S7/2) of Eu2+ was detected. The obtained values of chromaticity coordinates and absolute quantum yield are (0.644; 0.325) and ca. 1%, respectively. The phase transformations have been investigated using differential scanning calorimetry and thermogravimetry (50–1400 °C). After annealing in air at 700 °C, the monoclinic symmetry class of the Eu:Gd2O3 nanoparticles is preserved and the particle size increases to dm = 17.8 ± 6.1 nm. After annealing, the chromaticity coordinates (0.659; 0.334) and absolute quantum yield (ca. 4%) can be obtained using red phosphor based on monoclinic Gd2O3:Eu3+. The lifetime of the excited 5D0 state of Eu3+ in the annealed nanoparticles is longer than that in the as-synthesized nanoparticles, due to the suppression of nonradiative decay after annealing.
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